As disclosed in Patent Literature 1, vinyl chloride can be mentioned as a material structuring the artificial hair fiber. Vinyl chloride is used in artificial hair fiber due to its superior workability, low cost, and the like.
Regarding artificial hair fiber using vinyl chloride as its material, vinyl chloride resin was inferior in heat resistance against heat from hair iron and the like. When the artificial hair fiber was curled with the hair iron at its common temperature range of 100° C. or higher, fusion, crimp and the like of the fiber occur, resulting in cases where the fiber is damaged or cut.
Accordingly, it was difficult for the user to re-arrange the style arranged by the wig manufacturer into the user's preferable style. Therefore, the user basically had to use the wig with the originally arranged style, and thus there was a limitation in its usage.
In Patent Literature 2, artificial hair fiber prepared by threading a resin composition containing polyamide is disclosed. Polyamide is superior in terms of heat resistance and curl setting characteristics compared with vinyl chloride, and thus problems accompanied with artificial hair fiber made of vinyl chloride can be solved at a certain level.